1. Field of the Invention
The invention relates to an optical disk reading device, and more particularly to the optical disk reading device with an adjustable positioning element that can constrain and adjust guide rods efficiently.
2. Description of the Prior Art
Optical disk drives such as CD-ROM drives have been widely used in multimedia computer system, and more particularly for desktop computers. Most computer manufacturers regard the CD-ROM drives as the standard equipment shipped with their product. At present, the reading speed of optical disk drives have increased significantly with the development of optical data storage medium technology. However, the price of every optical disk drive is significantly lowered in recent years. Thus, for disk drives manufacturers, how to reduce the cost of assembly and key components is a challenge.
FIG. 1 shows an optical disk reading assembly 1a of a conventional optical disk reading device.
As shown in FIG. 1, the disk reading assembly 1a is embodied in the conventional CD-ROM drive. The disk reading assembly 1a is provided with a chassis 10a, a disk rotating module 20a, a disk reading module 30a, and two guide rods 40a. The disk reading module 30a is slidably mounted on two guide rods 40a. The two ends of each guide rod 40a must be respectively constrained by two holding pieces 50a fastened by screws 60a on the chassis 10a. If we would like to make sure the optical disk drive can read/write data accurately, then a tilt angle of the disk reading module 30a must be adjusted precisely. In this regard, the disk reading module 30a fails to do read/write operation accurately if the reading module 30a cannot receive the reflective laser beam from the optical disk because of an inaccurate tilt angle. Further, when an assembly worker adjusts the tilt angle of the disk reading module 30a, the assembly worker must fasten the two guide rods 40a by the four screws 60a beforehand. However, until the desirable tilt angle of the disk reading module 30a is determined, the two guide rods 40a are fixedly secured by the four screws 60a. If the assembly worker wants to adjust two guide rods 40a again, he must loose four screws and does the above procedure again. In prior art, the determination of tilt angle of the disk reading module 30a is tedious and time-consuming. Finally, the disk reading module 30a can slide along the guide rods 40a to read the data stored in the CD-ROM optical disk (not shown) that is placed on the disk rotating module 20a after the tilt angle is determined.
The optical disk reading assembly 1a of a conventional CD-ROM disk drive has the following disadvantages:
1. A plurality of holding pieces 50a are necessary to fasten the ends of two guide rods 40a, which results in increase of manufacturing cost, and
2. The additional holding pieces 50a require more assembly workers to assemble. Even worse, because the holding pieces 50a are thin and light, it is difficult and time-consuming for assembly workers to assemble the holding pieces 50a to the chassis 10a until the tilt angle is determined.
As mentioned, the disadvantages of the conventional optical disk unit must be overcome. Thus, there remains a need for an adjusting device that can constrain and adjust two guide rods with much less manufacturing cycle time and costs.
It is an object of the present invention to provide an optical reading with an adjusting device that can constrain and adjust guide rods efficiently.
It is another object of the present invention to provide a disk reading assembly with an adjusting device that can adjust the guide rods with three adjusting screws and resilience of the adjusting device. The present invention requires fewer components, thereby causing cost of manufacture to be decreased and complexity to be reduced.
According to the purposes of the present invention, a disk reading assembly has a chassis, a first guide rod, a second guide rod, an adjustable positioning element, a clamping plate, a disk rotating module and a disk reading module. Each end of the first guide rod and the second guide rod are respectively disposed on the chassis. One end of the second guide rod is fixedly secured to the chassis. The adjustable positioning element constrains two ends of the first guide rod and the other end of the second guide rod respectively. The clamping plate is used to restrain a portion of the adjustable positioning element on the chassis. Therefore, two guide rods can be mounted and adjustable on the chassis by the three adjusting screws and resilience of the adjustable positioning element.